Top 10 lists
are appealing, from top 10 books to top 10 YouTube videos to "top
10 news items you are not looking forward to this month," which for
me would include political ads and hearing whether Lindsay Lohan is in
or out of rehab. Getting young people to think about the environment is
a worthwhile goal, and listing the top 10 environmental problems could
be a good classroom exercise for grammar school through high school.

My top 10
environmental problems are listed below in order of increasing importance.
The list has changed little from a consolidation of views by my ecology
graduate students five years ago.

10. Air pollution.
Uncontrolled releases by industry and the excessive use of fossil fuels
have led to acid rain, dissolution of the ozone layer, smog and the general
elimination of "clean air."

9. Invasive
plants and animals. The problems resulting from fire ants, Burmese pythons
in the Everglades and many more regional environmental problems have a
human origin related to the introduction of exotic species.

8. Global
climate change. Although "global warming" receives a lot of
press, as Brian Todd of the University of California, Davis, pointed out,
"the global climate for the past 4 billion years has been one marked
by change and relative instability. The problem we face today is the crippled
ability of many ecosystems to appropriately respond to climate change
as they have [in the past] because we have already compromised the environment
in other ways."

7. Pollution
of marine habitats. The oceans are huge, but overharvesting and the degradation
of marine environments are proceeding at a steady rate around the world,
including a commercially extinct codfish industry and disappearing coral
reefs along our coasts. The recent BP oil disaster obviously comes to
mind when the words "ocean" and "pollution" are mentioned.

5. Threat
of disease. Swine flu, West Nile virus and mad cow disease are examples
of ways we can be affected by unseen enemies. All are a consequence of
human overcrowding, overconsumption and invasive species.

4. Water
quality and quantity. Sewage from cities, unregulated releases from industrial
and agricultural sites, and dumping of wastes in the oceans collectively
exacerbate the worldwide problem of water pollution. In many coastal regions,
overuse of groundwater, which leads to saltwater intrusion, is a looming
specter. Water wars are now a reality in the western states and even in
the wetter Southeast, as evidenced by court cases involving Alabama, Georgia
and Florida.

3. Habitat
loss, fragmentation and degradation. The loss of natural habitats because
of human development and deforestation is a major cause of the decline
in biodiversity nationally and globally. Many species are on an inexorable
path toward extinction because their native habitats are gone or despoiled.

2. Human
overpopulation. Unchecked human population growth leads to overconsumption
and associated world poverty. Many people would rank overpopulation as
the no. 1 cause of our other environmental problems. Virtually every problem
above can be traced back to our simply having too many people for the
resources available. Until political and religious leaders have the courage
to address the issue of birth control on a global scale, most of our environmental
problems will worsen before they get better.

1. Political
apathy. I consider this the no. 1 reason that the nine other environmental
problems listed here are not being properly addressed. A clear indicator
of this problem is that world leaders seldom acknowledge, let alone propose
solutions to, environmental problems. For those leaders around the world
chosen by a democratic election process, voters are not just condoning
such apathy, they are participating in it.

What would
schoolchildren consider to be the top 10 environmental problems facing
the United States and the world? Having a class offer their views should
generate some interesting discussions. And one thing is certain, until
we overcome our apathy, we will never overcome our other problems--environmental
or otherwise.